As a conventional device for projecting an image to a wall surface or a screen, a so-called projector is used. A mainstream of the projector is a so-called stationary type device which is supplied with power from a commercial power supply and is used when it is fixed to a predetermined location. A projector as the stationary type projects, in its fixed state, an image to a given portion of the wall surface or to the screen.
Recently, on the other hand, a mobile projector compact in size and easy to carry is proposed as the projector. For example, Patent Literature 1 describes a mobile terminal with a projector function which incorporates a projector that includes an upper cabinet, a lower cabinet, and a hinge portion for mutually pivotally connecting the upper cabinet and the lower cabinet and that has a lens and a light source.
This type of mobile projector can easily change an area to which an image is projected by the projector. That is, the projector can easily change a light irradiation direction. Therefore, the light may be unintentionally irradiated to a person. Because the projector irradiates high-intensity light, if the light irradiated from the projector directly enters person's eyes at a close position, the person is very dazzled by the irradiated light.
In terms of this point, for example, Patent Literature 2 describes a mobile communication terminal with a projection function that includes a projector for projecting projection data, a detector for detecting a state of the mobile communication terminal, a movement determining unit for determining whether there is any change in the state detected by the detector, and a control unit for sending the projection data to the projector. The mobile communication terminal is capable of controlling a light amount when a person enters a projected light area by transmitting control data for controlling a light amount to be projected by the control unit when the movement determining unit determines that there is a change in the state of the terminal.